Because in a 35 weeks fit of insanity I've advance ordered one. Despite having a normal Integra, a Beco Butterfly and a Manduca 
We'll be spending most of the summer in France with ILs with a single pushchair, so one of the DSs will need to be carried. Last year we had DS1 in the Manduca in France and it was so hot and sweaty - so will this be a good option? Please say yes!
Oh dear, I'm having impulse buyer's remorse...